The 27-year-old moved to Exeter from the Ospreys in 2011 but has struggled with chest and shoulder injuries over the last two seasons.

He is heading back over the Severn Bridge to the Arms Park with the aim of forcing his way back into the Wales squad and adding to his 15 caps.

Mitchell said: "It's not quite worked out how I would have wanted because of the injuries. In an ideal world I'd love to have played more, simply because the Chiefs are a great club.

"At the same time I've been offered a great opportunity with the Blues and it's one that I am looking forward to.

"For me it's a chance to go home and try to kick-start my career again. One of my aims is obviously to try to get back into the Wales squad, but the boys who have come in have done well so it's going to be tough.

"I know I will have to work hard to try to do that, but I am willing to put myself through the pain barrier to get back in."

Adam Jones, Samson Lee and Rhodri Jones are the tightheads named in Warren Gatland's Six Nations squad.